Microwave power limiters based on RF-MEMS

This paper presents a novel application of MEMS to RF signals: microwave power limiters. A 10.24GHz RF-MEMS based limiter with a 28.2dBm threshold power and a dynamic range of more than 8dB is presented limiting the output power to 27.5dBm with 0.65dB insertion losses. For low power applications, the output limited power can be decreased by biasing RF-MEMS. By biasing the device at 5.2V (V_p = 5.6V), a 10.24GHz power limiter with a 14.2dBm threshold power and a dynamic range of more than 13dB is obtained and the limited output power is only 13.8dBm. Losses of the biased limiter are 1dB. Simulations of a Computer Aided Design (CAD) integrated behavioral model of capacitive RF-MEMS switch have been compared with measured data with good agreement.